Composition for pattern formation, and pattern-forming method

Abstract

A composition for pattern formation includes a block copolymer. The block polymer includes a first labile group at an end of a main chain of the block copolymer. The first acid liable group is capable of being dissociated by an acid or heat. The composition preferably further contains an acid generator that generates an acid upon application of an energy. The block copolymer is preferably capable of forming a phase separation structure through directed self-assembly. The first labile group is preferably represented by formula (a). R represents a monovalent organic group having 1 to 20 carbon atoms; R′ represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; and * denotes a binding site to an atom at the end of the main chain of the block copolymer.

What is claimed is: 
     
       1. A composition, comprising:
 a block copolymer that comprises a first acid labile group at an end of a main chain of the block copolymer, the first acid labile group being capable of being dissociated by an acid or heat; and 
 a solvent, 
 wherein the first acid labile group is a carboxy protecting group with which a hydrogen atom of a carboxy group is substituted, a hydroxyl protecting group with which a hydrogen atom of a hydroxy group is substituted, or both thereof, 
 the carboxy protecting group is at least one protecting group selected from the group consisting of a trialkylsilyl group, a 1-alkoxyalkyl group, a cyclic ether, and an alkyl group having a quaternary carbon atom represented by formula (i), and 
 the hydroxy protecting group is at least one protecting group selected from the group consisting of a group forming an acetal structure, and an acyl group: 
 
       
         
           
           
               
               
           
         
         wherein R p1  represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; R p2  and R p3  each independently represent a monovalent chain hydrocarbon group having 1 to 20 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R p2  and R p3  taken together represent an alicyclic structure having 3 to 20 ring atoms together with the carbon atom to which R p2  and R p3  bond; and * denotes a binding site to an oxygen atom of the carboxy group. 
       
     
     
       2. The composition according to  claim 1 , further comprising an acid generator that generates an acid upon application of an energy. 
     
     
       3. The composition according to  claim 1 , wherein the block copolymer is capable of forming a phase separation structure through directed self-assembly. 
     
     
       4. The composition according to  claim 1 , wherein the first acid labile group is represented by formula (a): 
       
         
           
           
               
               
           
         
         wherein in the formula (a), 
         R represents a monovalent organic group having 1 to 20 carbon atoms; 
         R′ represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; and 
         * denotes a binding site to an atom at the end of the main chain of the block copolymer. 
       
     
     
       5. The composition according to  claim 1 , wherein the block copolymer comprises:
 a first block that comprises a first structural unit comprising a styrene structure; and 
 a second block that comprises a second structural unit comprising a (meth)acrylic acid ester structure. 
 
     
     
       6. The composition according to  claim 5 , wherein the first acid labile group is present at an end of a main chain of the second block. 
     
     
       7. The composition according to  claim 5 , wherein the block copolymer comprises a crosslinkable structural unit that comprises a crosslinkable group on a side chain thereof. 
     
     
       8. The composition according to  claim 7 , wherein the first block comprises the crosslinkable structural unit. 
     
     
       9. The composition according to  claim 5 , wherein the block copolymer further comprises a second acid labile group on a side chain of the block copolymer, the second acid labile group being capable of being dissociated by an acid or heat. 
     
     
       10. The composition according to  claim 9 , wherein the second block comprises the second acid labile group. 
     
     
       11. A pattern-forming method comprising:
 applying a composition directly or indirectly on a substrate to provide a first film; 
 exposing the first film; 
 providing a second film on the first film, the second film being a directed self-assembling film comprising a phase separation structure which comprises a plurality of phases; and 
 removing a part of the plurality of phases of the second film, 
 wherein the composition comprises:
 a block copolymer that comprises a first acid labile group at an end of a main chain of the block copolymer, the first acid labile group being capable of being dissociated by an acid or heat; and 
 a solvent. 
 
 
     
     
       12. The pattern-forming method according to  claim 11 , further comprising:
 forming a prepattern directly or indirectly on the substrate, 
 wherein the second film is provided after forming the prepattern. 
 
     
     
       13. The pattern-forming method according to  claim 11 , wherein a line-and-space pattern or a hole pattern is formed. 
     
     
       14. The pattern-forming method according to  claim 11 , wherein the first acid labile group is a carboxy protecting group with which a hydrogen atom of a carboxy group is substituted, a hydroxyl protecting group with which a hydrogen atom of a hydroxy group is substituted, or both thereof,
 the carboxy protecting group is at least one protecting group selected from the group consisting of a trialkylsilyl group, a 1-alkoxyalkyl group, a cyclic ether, and an alkyl group having a quaternary carbon atom represented by formula (i), and 
 the hydroxy protecting group is at least one protecting group selected from the group consisting of a group forming an acetal structure, and an acyl group: 
 
       
         
           
           
               
               
           
         
         wherein R p1  represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; R p2  and R p3  each independently represent a monovalent chain hydrocarbon group having 1 to 20 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R p2  and R p3  taken together represent an alicyclic structure having 3 to 20 ring atoms together with the carbon atom to which R p2  and R p3  bond; and * denotes a binding site to an oxygen atom of the carboxy group. 
       
     
     
       15. A pattern-forming method comprising:
 applying a composition directly or indirectly on a substrate to provide a first film that is a directed self-assembling film comprising a phase separation structure which comprises a plurality of phases; 
 exposing the first film; and 
 removing a part of the plurality of phases of the first film, 
 wherein the composition comprises:
 a block copolymer that comprises a first acid labile group at an end of a main chain of the block copolymer, the first acid labile group being capable of being dissociated by an acid or heat; and 
 a solvent, and 
 
 wherein the block copolymer is capable of forming a phase separation structure through directed self-assembly. 
 
     
     
       16. The pattern-forming method according to  claim 15 , further comprising:
 providing a second film on the first film, the second film being a directed self-assembling film comprising a phase separation structure which comprises a plurality of phases; and 
 removing a part of the plurality of phases of the second film. 
 
     
     
       17. The pattern-forming method according to  claim 15 , further comprising:
 forming a prepattern directly or indirectly on the substrate, 
 wherein the first film is provided after forming the prepattern. 
 
     
     
       18. The pattern-forming method according to  claim 15 , wherein a line-and-space pattern or a hole pattern is formed. 
     
     
       19. The pattern-forming method according to  claim 15 , wherein the first acid labile group is a carboxy protecting group with which a hydrogen atom of a carboxy group is substituted, a hydroxyl protecting group with which a hydrogen atom of a hydroxy group is substituted, or both thereof,
 the carboxy protecting group is at least one protecting group selected from the group consisting of a trialkylsilyl group, a 1-alkoxyalkyl group, a cyclic ether, and an alkyl group having a quaternary carbon atom represented by formula (i), and 
 the hydroxy protecting group is at least one protecting group selected from the group consisting of a group forming an acetal structure, and an acyl group: 
 
       
         
           
           
               
               
           
         
         wherein R p1  represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; R p2  and R p3  each independently represent a monovalent chain hydrocarbon group having 1 to 20 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R p2  and R p3  taken together represent an alicyclic structure having 3 to 20 ring atoms together with the carbon atom to which R p2  and R p3  bond; and * denotes a binding site to an oxygen atom of the carboxy group.